


Cavity

by SaraJaye



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Alternate Universe - Modern Setting, Anxiety, Dentists, Felix Has Issues, Gen, Hurt/Comfort, Mercedes is a good big sister, Toothache, blended families - Freeform, cavities
Language: English
Status: Completed
Published: 2021-01-04
Updated: 2021-01-04
Packaged: 2021-03-14 21:27:44
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,595
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28552356
Author URL: https://archiveofourown.org/users/SaraJaye/pseuds/SaraJaye
Summary: In which Felix's first cavity leads to Deep Psychological Issues because blended families are a lot to get used to and Felix is Felix. And Mercedes can never turn down the chance to help someone she loves.
Relationships: Felix Hugo Fraldarius & Mercedes von Martritz
Kudos: 8
Collections: Hurt/Comfort Bingo - Round 11





	Cavity

**Author's Note:**

> Angela is the name I gave Mercedes and Emile's mother for this AU. Byron is male!Byleth.

When Felix was in preschool, his class had taken a tour of a dentist's office and watched a video about dental hygeine. It was the basic "candy rots your teeth so never touch it, eat your vegetables, and brush every day" lesson, and tiny Felix had gloated about how he didn't like most candy anyway so he'd _never_ get a cavity.

Until today, he'd been right. Apparently, sugar wasn't the only thing that caused cavities. Pickled radishes could do the job just fine if you ate them too much.

"It's not like having the chicken pox at this age," his father said as his stepmother dished up scrambled eggs and toast that only qualified as such due to having _been_ in the toaster for a minute. "So there's no need to be embarrassed about it. And besides, it could be worse."

"I'm _not_ embarassed," Felix muttered, forcing himself to take a bite of the eggs.

"At least you caught them early, dear," Angela said. Actually, it was Glenn, during a weekend visit home; Felix had made the mistake of wincing while he bit into a cracker, and Glenn, being the overprotective _ass_ he was, insisted on giving him a back-alley dental exam with a flashlight the tip of his gloved finger. And found the cavity in half a second.

"And at least you'll get the day off from school, right?" Mercedes said cheerfully as she dumped practically half the jar of strawberry jelly onto her toast. Felix shrugged, eating slowly, using only the right side of his mouth. He'd get out of history and literature class, and luckily he didn't have any tests coming up in either.

Even if he'd rather take a test than have a drill in his mouth. Having heard those things from down the hall during his checkups, he always felt smug knowing he wasn't the one being drilled.

"I'll have to sit out of gym class," he muttered. "You know how the nurse is, if you've so much as scraped your knee that morning she makes you sit quietly in her office and study." Actually, Ms. Casagranda wasn't _that_ bad, but she counted dental work as surgery. The day Ashe had his braces put on she'd made him sit out because he'd complained of them hurting his mouth, even though he insisted he could still run laps and do stretches.

"You can make up for it after school and you know that," Emile said.

"Of _course_ I know that."

"Felix, this was the only time Dr. Carroll could fit you in," Angela reminded him.

"That's right, and you'll feel much better afterwards," Mercedes added, polishing off her mountain of jelly with a little bit of toast underneath. Felix rolled his eyes, putting his fork down and crossing his arms over his chest.

"Y'know, it's really not fair. A girl who puts away the sweets like there's no tomorrow has perfect teeth, while I never touch any of that stuff and I've gotta get a filling," he muttered. "I thought radishes were supposed to be good for you. After this I bet Dr. Carroll tells me I shouldn't eat them anymore and make all of you watch me like a hawk to make sure I don't."

"The doctor didn't even say it was the radishes," Emile said, sipping his orange juice. "I think you just have bad luck."

"Emile!" Mercedes scolded. "Now's not the time to make such jokes."

"He's being a drama queen," Emile said. Felix glared at him.

"Just because you think you're too edgy for feelings-"

"And you don't?"

"Knock it off, you two," Father scolded. "Emile, isn't it almost time to meet Byron at the bus stop?" Emile turned red, wolfed down the rest of his breakfast, then rushed to grab his books and head out the door, stopping only to kiss his mother and Mercedes goodbye. Emile liked to leave early, period, but especially when he got to walk with Byron Eisner.

"Finally," Felix muttered, pushing his plate away. "My appointment's not for fifteen minutes, I'm going upstairs."

"Wait, Felix." Mercedes wiped her mouth and followed him upstairs, putting a hand on his shoulder. "You shouldn't let Emile get to you so much. He's just not great with most people, and he's still not used to having brothers, especially one so close to his age. Not that I'm making excuses-"

"It's not him. Trust me, I'm not afraid of some whimpering puppy in a wolverine's body." Felix sighed. "Even if I wish he'd shut up."

"I understand. You're scared about your first filling, it's natural for you to be on edge," Mercedes said. Felix bristled, jamming his fist into his pocket.

"I'm _not_ scared," he muttered. "Don't go putting feelings in me that aren't there, like the time Ingrid and Sylvain wouldn't shut up about how I was jealous of Molinaro being the boar's new best friend."

"But you were." Felix twitched, stomping into his room, Mercedes following him before he could close the door.

"Well, this is different," he said. "I'm not scared of some stupid noisy dentist's drill, I just don't want it anywhere near my mouth! What if it slips? What if he drills too deep and hits a nerve, or he screws up and I wind up with my jaw wired shut or my whole head in bandages?!"

Her face turned sickeningly sympathetic, and he cursed his lack of a filter. _Stupid, that last thing only happens in cartoons! You just sounded like a stupid little kid who's never been to a damn dentist before!_ Of course, the first two things were still possible, and the hole in his tooth hurt even more just thinking about them.

"I thought so," she murmured, and Felix sighed, flopping down onto his bed.

"So go ahead, give me the big speech about how it's okay to be scared and how I've got nothing to worry about," he sighed. "Might as well be you, Glenn's not here and it's still a _little_ less humiliating than having it come from Dad or Angela." Mercedes patted him on the shoulder.

"Felix, if I gave you that speech, would it make you feel better?" she asked.

"Fuck no."

"Then I won't," she said. "Instead, I'll tell you that you've known Dr. Carroll since you were a child and he's never made a mistake. I'll also tell you that _nobody_ likes the sound of a dentist's drill." She laughed. "Even with my teeth being as _perfect_ as they are, I've heard it too. It's even worse in real life than on TV! But, well, maybe Dr. Carroll will let you wear your ear buds to muffle it."

"Maybe." Felix sat up. "I just don't like that this bothers me so much period, especially when so many people can _tell_ it bothers me. Sometimes it feels like you and your mom want to smother me because you think I'm just a sad little boy inside and I _hate_ feeling smothered! Glenn's the only one who knows how to fuss over me without it being annoying."

"Because you're not used to us yet," Mercedes said. "I understand, Felix. Sometimes it still feels strange for your father to worry about me, because my father died when I was so young and I got used to splitting the parental role with my own mother. And you've seen the way Emile gets when Glenn tries to be brotherly to him, or your father tries to be nice to him."

Felix sighed, running a hand through his hair.

"Exactly. And having a cavity on top of all this pisses me off even more," he muttered. "It's bad enough that Ms. Casagranda won't let me take gym today, but..."

"Mother won't make you rest on the couch after school, and she won't serve soft, boring foods for dinner, I promise," Mercedes said. "In fact, don't be surprised if she makes your favorite pulled pork sandwiches. She'll want to spoil you a bit." Felix grinned. Emile hated pulled pork sandwiches.

"I can live with that." Mercedes squeezed his shoulder.

"See? There's an upside to this after all!" Felix shook his head, still smiling.

"Let the dentist put a noisy drill in your mouth and you get meat?"

"Exactly!" Mercedes smiled. "Feeling better now?"

"A little. Actually, I'd probably have felt better from the start if you'd skipped all that psychologist talk and just told me I'd get food as a reward for putting up with this," Felix said. Mercedes laughed.

"Well, I do want to be a psychologist when I grow up. That or a baker," she said. "So I'm glad I could help." Felix rolled his eyes. This whole thing felt _stupid,_ an impromptu therapy session about a toothache, but Mercedes was gonna be Mercedes and she was right. This whole situation was a lot to deal with, and he was sure if she were the one with the cavity on top of everything else she'd be upset, too.

"As far as sappy, smothering big stepsisters go, you're pretty great," he conceded. "If only _you_ could take me instead of Dad, but..."

"But I'm running late for school as it is." She hugged him, and after a moment he hugged her back. "I'll see you later." She headed downstairs. Felix grabbed his bookbag, his coat, and put his shoes on to wait outside for his father. The cold air outside made the ache in his molar even worse, and he shoved his hands in his coat pockets.

_Pickled radishes are expensive and take forever to make anyway._


End file.
